At the recent Camp David summit between Tony Blair and President Bush, the news conference was packed and the overflow press corps listened from a big room, British and Europeans separated from their American colleagues by a thin partition.
The Americans shuffled with outraged incomprehension as the Brits howled with laughter at President Bush's verbal infelicities.
Tony Blair's influence on George Bush has been 'huge'
British ministers loyal to Tony Blair say it's this sort of snobbishness that has made it so difficult for the prime minister to gather support for war in his country and in his party.
They fulminate that something doesn't automatically become wrong because President Bush supports it.
But how much is this coincidence of interest and how much is it an agreement?
After the war is over Tony Blair will be judged by the country on its success or failure.
But he may be judged by his party and his closest colleagues on the peace. On what comes next. On his motives. The question they might ask is "Is Blair really a neo-conservative?"
It is the neo-conservatives in President Bush's cabinet, Donald Rumsfeld and Dick Cheney, who have long argued for this war.
'21st Century Nationalists'?
In 1997 they, along with Jeb Bush, Paul Wolfowitz and Dan Quayle, signed the founding document for the neo-conservative "Project for the New American Century".
They argued that America has to re-discover its "military strength and moral clarity" and needed to "challenge regimes hostile to our interest and values".
They had to wait, but they've got their way.
Jeb Bush signed founding document for a neo-conservative project
For a couple of weeks I've been trying to find out, without success, why the neo-conservatives are so labelled.
There's not much "neo" about them.
Better names might be "Pre-emptive Pragmatists", "Armed Might Paternalists" or perhaps "Imperialist Aggressors". Ha ha. Only joking.
They are at any rate full blooded 21st Century Nationalists. They believe that "American leadership is good for America and good for the world".
They think that American defence spending is too low, and that as the only super power America must remain militarily unchallenged.
In the heyday of the British Empire the navy had a formula that it must remain larger than the next two forces combined.
Some neo-cons have updated the doctrine to suggest that the US has the right to pre-emptively deal with any state that has the temerity to come close.
Rumsfeld has long argued for taking on Iraq
Tony Blair hasn't explicitly endorsed this view of the world. But he's come close. He's shown plenty of passion over this war.
But the three moments of highest passion I've seen recently were off the cuff, in defence of America's leading role in the world.
Mr Blair argues that America is a force for good in the world and seems terrified of a "bipolar world" - code for other Western powers, with similar values arguing a different case to the US administration.
There is one way in which the neo-cons are hugely different to previous nationalists. They insist America's mission is to bring democracy to the world.
True, they don't spend their time organising worthy summer schools for opposition politicians in emerging democracies.
I hunt in vain for an earnest neo-con pamphlet debating whether first past the post or proportional representation would be better for a Democratic Iraq.
Europeans and Americans take different stance on UN
Their commitment to democracy is, shall we say, a muscular optimism: states that oppose their values should be "challenged". Shake the kaleidoscope vigorously enough and a more pleasing pattern will emerge.
Tony Blair has been an explicit champion of this rather unconservative view that the day of the sacrosanct nation state is over.
We have the right to interfere to prevent genocide, massacre, and on occasions, general bad behaviour. He argues forcefully that unruly dictatorships and countries on the edge of chaos are the biggest threat to the world.
The best guarantor of safety for the West is the spread of democratic states. But the second best is military force to remove the cause of instability and impose stability.
But there's one gaping hole in my argument. Surely, where Tony Blair and the neo-cons part company is their distain for international institutions, whether it's the UN or the International Court, and his belief in the importance of America working with the rest of the world?
But this is a caricature of their true position. Neo-cons are anything but stupid. They want as broad alliances as possible; they just don't want the will of America to be ultimately stopped or contained by such organisations.
Blair may not really be a neo-con ... but you know the old saying 'if it walks like a duck and quacks like a duck'
An important article by the leading neo-con Robert Kagan, written while Tony Blair was trying to get a second resolution, argued forcefully that even American multilateralists were unilateralists at heart.
It said of Europeans: "They have this idea that the UN Security Council is the only world body legally empowered to decide whether Iraq is to be invaded", whereas nearly all Americans believe of the UN: 'If it makes the right recommendation it strengthens your case. If not you can always ignore it.'"
There seems little doubt which side of this argument Mr Blair has come down on.
Downing Street has long argued that Tony Blair's influence on President Bush has been huge, delaying on Afghanistan for a UN mandate, trying to do the same for Iraq.
But at least one book detailing the course of the Afghan Conflict, "Bush at War" by Bob Woodward, shows the US War Cabinet waiting and waiting ... not for the UN ... but for the military to get their act together.
When they had, they went in. I suspect the Iraq campaign was not much different.
The next test is of course who runs Iraq after Saddam: the UN or the Americans.
But a much bigger test is what follows on the international stage.
Neo-cons see Iraq as a stepping stone to "confronting" other miscreant states. The Foreign Office scoff at the idea Iran could be in Blair's sights.
They argue Britain has quite deliberately bucked the American line and is in the business of building bridges, not dropping bombs.
The same is true of Syria, they say. And North Korea must have a diplomatic solution. But in public at least Tony Blair has not moved one inch from his contention that rogue states, and those with illegal weapons of mass destruction must be dealt with.
So is Blair a neo-con? Well not really, he comes from a different perspective and different tradition.
At the end of last year I was convinced by the notion that Blair was caught in a paradox: he believed in a new world order of democratic and liberal values, backed by the international rule of law, enforced by the only power capable of playing global policeman.
The paradox was that the policeman often had to be cajoled to play within the rules. Now I'm not so sure.
Blair may not really be a neo-con ... but you know the old saying "if it walks like a duck and quacks like a duck"...
It may be an image that goes down better in Middle America than with Labour's grassroots, but if the war goes wrong there are plenty of Labour MPs polishing their 12 bores and hoping feathers will fly.